Depending on the intensity of exposure, the immune status of the exposed individual, and the underlying lung architecture of the host, disease can range from asymptomatic to life-threatening.

• Immunocompetent pts usually have asymptomatic or mild and self-limited disease.
  • - Approximately 1-4 weeks after exposure, some pts develop a flu-like illness with fever, chills, sweats, headache, myalgia, anorexia, cough, dyspnea, and chest pain. 5-10% of pts with acute histoplasmosis develop arthralgia or arthritis, often associated with erythema nodosum.
  • - Hilar or mediastinal lymphadenopathy may occur and can cause vascular or tracheoesophageal compression.
• Immunocompromised pts, who are more likely to develop progressive disseminated histoplasmosis (PDH), account for ~70% of cases.
  • - The clinical spectrum ranges from a rapidly fatal course with diffuse interstitial or reticulonodular lung infiltrates, shock, and multiorgan failure to a subacute course with focal organ involvement, hepatosplenomegaly, fever, and weight loss.
  • - Meningitis, oral mucosal ulcerations, GI ulcerations, and adrenal insufficiency can occur.
• Chronic cavitary histoplasmosis most often affects smokers with structural lung disease (e.g., emphysema) and presents as productive cough, dyspnea, low-grade fever, night sweats, and weight loss.